By L. Akrabor. Midwestern State University. 2019.
This manipulation of germ cells and embryos that occurs in vitro purchase minocycline 50mg line antibiotics for uti guidelines, especially at such an early crucial point in development buy 50mg minocycline overnight delivery bacteria reproduce asexually by, therefore demonstrates the fragility of the epigenome compared to the genome trusted 50mg minocycline bacteria stuffed animals, exemplied by this specic abnormality at an imprinted locus buy 50mg minocycline mastercard infection 2. There is considerable variation in estimates of the actual level of imprinted regions in the mammalian, including the human, genome. Recent evidence has hinted at the possibility of high levels of particular brain tissue-specic imprinting in a mouse model . Soitis plausible that there is still an underestimation of imprinted loci, particularly with the inclu- sion of tissue-specic and developmental-stage-specic variation. Moreover whilst there is as yet no denitive set of human or other eutherian mammalian imprinted genes, there does appear to be signicant dissimilarities between the species. These differences could be reconciled with the paternal conict theory, for instance, as being driven by variation in litter size between mouse and human . This includes the paternally expressed genes Dlk1 (delta-like 1 homolog, Drosophila), Mest (mesoderm specic transcript) (also known as Peg1) and Ndn (Necdin) . Two further paternally expressed genes Mest(Peg1) and Peg3 are involved not only in fetal and postnatal growth, but also can affect maternal nurturing success [77,78]. These imprinted genes are strongly expressed in hypothalamus, preoptic area, and septum, therefore they are excellent candidates for neuronal programming . Metastable epialleles are so termed as these loci of epigenetically variability are established very early in embryogenesis and subsequently remain stable whilst permeating through all ensuing developmental stages and germ layers . In the wild-type mouse the Agouti gene encodes a signaling molecule that produces either black eumelanin (a) or yellow phaeomelanin (A). Transcription is normally initiated from a hair- specic promoter in exon 2, with transient expression of the A allele leading to the mottled brown fur. This overaction results in a lightening of the coat color as ectopic expression of the inverse agonist at melanocortin receptors, agouti, antagonizes the action of melanin . The viable yellow heterozygote vy (A /a) mouse has a shortened live span with yellow fur, obesity, and an increased suscep- tibility to neoplasia . Dietary impact on imprinted genes nevertheless has been documented, in the imprinted Igf2 locus in a mouse model . Instalment of a methyl-donor-decient diet post-weaning led to loss of imprinting at this locus with subsequent modication of expression. The inbred mouse strain C57Bl/6J is documented as being highly susceptible to diet-induced obesity, but furthermore has also been observed to show a wide range of variability in this weight gain when fed a high-calorie diet . Phenotype divergence into those who would become high weight-gainers versus low was even evident in measures before commencing an obesity- 280 promoting diet. Additionally these dissimilarities persisted even when the mice were switched back to a calorie- restricted diet. Overfeeding in rats, induced by limiting the litter size, led to an obese phenotype . Leptin and insulin stimulate this pathway via two Sp1-related binding sequences within this promoter. This can be perceptibly displayed by the observation that the common genetic susceptibilities towards the trait are not acted upon, unless certain compounding causes are encountered. Lifestyle contributors such as diet and exercise are central in liability to metabolic disease and also have a substantial aggregate effect . It has been proposed that the etiology of common diseases are under both genetic and epigenetic inuence and these disease-related epigenetic factors could be environmentally induced with subsequent modulatory effects on genetic susceptibility . Epigenetic effect on gene expression by the modication of the target cell epigenome , thereby changes metabolic risk [79,94]. The signicant role of epigenetics in the pathogenesis of cancer is well established  but has also been seen in other diseases such as in the etiology of athero- sclerotic plaques , and evidence is accumulating in the metabolic syndrome. This may be caused by accrued environ- mental effect and/or epigenetic drift due to defective transmission through multiple mitotic replications. Therefore it has been speculated these shifts may modify metabolic path- ways, becoming gradually suboptimal, leading to slow late-onset weight gain . The major stages are at postfertilization and at germ cell differentiation in males and females. Experimental evidence in mice shows that the preimplantation embryo is sensitive to epigenetic modications . Direct evidence of dietary modulation during these time-points, and the latent ability to affect long-term risk of chronic metabolic disease health has been attempted using murine models, through from the periconceptual period to postweaning . The epigenetic state of the transcription factor Hnf4a was investigated in the pancreas of rats that had been subjected to poor maternal diet and controls . Poor maternal diet during critical periods of development, as well as aging, was shown to down-regulate an islet-specic promoter and the interaction between the promoter and an enhancer was also down-regulated. Cellular memory in the pancreatic cells of the developmental intra- uterine environment was sought by the investigation of approximately 1 million CpG sites in the rat methylome of these cells at the later age of 7 weeks. This proposes that the peri- conceptual, in utero, and postnatal developmental environment can impact on long-term risk for adult-onset disease by set point adaptive changes [109e111]. This suggests that poor nutrition at critical growth stages increases the chance of developing the metabolic syndrome (insulin resistance, obesity, dyslipidemia, and hypertension) in later life and these develop- mental origins of adult disease put forward epigenetic inheritance as the possible mechanism 282 in this programming . Although ischemic heart disease increases in a population as it becomes wealthier, it was noted that those in the poorest regions suffered disproportionately . An early epidemiological study in England and Wales identied a connection between poor nutrition in early life and increased susceptibility to ischemic heart disease, that was suggested to be due to a more detrimental effect of an adiposity-promoting diet in these individuals . Furthermore, impaired glucose tolerance in men aged 64 was correlated to low weight at birth and at 1 year . Documented historical famines furthermore allow these questions to be proposed to age cohorts, and the Dutch Hunger Winter of November 1944 to May 1945 has been a classic example in the literature. Upon reaching the army draft age of 19 years the obesity rates of 300 000 men were compared . The outcomes were dependent on when during their development the severe wartime famine had occurred. Those exposed in the last trimester or the rst months of life were less likely to be obese, whilst those whose mothers had been in early or mid-pregnancy during this severe wartime famine were twice as likely to be obese at army draft. This would imply early changes may differ in programming from later changes, tting with hypotheses of developmental programming and critical epigenetic windows. Individuals conceived during the famine were compared against a sibling of the same sex to attempt to reduce environmental and genetic modulators. Follow-up work investigated a further 15 loci with known involvement in growth and metabolism . These studies have highlighted the periconceptual period as a volatile spatiotemporal window in epigenomic development with additional support for this coming from animal models . Manipulation of dietary vitamin B and methionine during this periconceptual period in sheep led to heavier, fatter, and insulin-resistant animals . In a large population-based obesity study, the maternal impact on this trait was shown to be greater , possibly due to maternally imprinted genes. As these imprinted loci are strongly interconnected with resource allocation, energy balance, and feeding behavior, early envir- onmental effects may have long-reaching consequences. This makes these parental-specic marks obviously strong initial candidates in any fetal programming or plasticity inuence on chronic disease. It may be that these imprinting resource allocation tools are subverted by the fetal programming mechanism, enabling a shift of resource regulation over the course of a lifetime and subsequent risk for adult-onset disease . This metabolic plasticity enables a non-changed genome to produce a range of phenotypes in response to variation in envir- onment, specically early nutritional status [121,122]. Subtle modulation of imprinting pathways could be a mechanism, or it may be that they are too critical for an adaptive process and changes are only seen in severe disease manifestations .
Each of these hospital utilization were available (1995 and 1998) purchase 50 mg minocycline free shipping infection movie, settings was analyzed separately minocycline 50 mg for sale antimicrobial cutting boards. Hispanic men had the highest rates of utilization purchase minocycline 50 mg otc antibiotics for sinus infection side effects, followed by African American men discount minocycline 50mg antibiotics questions pharmacology. The reason for likely refects the higher incidence and prevalence this observed difference is unclear. The reasons for the dramatic increases in 1992 and 1996 are unclear but may be Physician Offces related to coding anomalies. Rates in the most elderly more than 1,290,000 were for a primary diagnosis of cohort (95 and older) were similar to the overall mean. In these years, the observed rates of physician over time and were least pronounced in 1998. This rates of physician offce utilization among the racial/ 196 197 Urologic Diseases in America Urinary Tract Infection in Men 198 199 Urologic Diseases in America Urinary Tract Infection in Men Table 12. Rates were highest in the 2000 was 442 per 100,000, which is similar to the rate Midwest and Northeast and lowest in the South and of 420 per 100,000 observed in 1994. Trends in visits by males with urinary tract infection listed as primary diagnosis by patient age and site of service, 1998. In all years studied, about half of male nursing home The lowest rates were observed in Asian men. Rate of emergency room visits for males with urinary tract infection listed as primary diagnosis by patient race and year. Although these rates of skipped at a much higher rate that year, making its catheter and ostomy use are not dramatic, they are results diffcult to interpret (Table 17). The rates of indwelling catheter and ostomy use Direct Costs in male nursing home residents have remained stable Urinary tract infections in men are associated at 11. Men with pyelonephritis also missed health care expenditures for men and women with more total time from work than did women (11. Fluoroquinolones accounted for a large portion each ambulatory care visit or hospitalization for of these expenditures, in terms of both costs and orchitis, men missed an average of 3. Including expenditures on these excluded medications would increase total outpatient drug spending for urinary tract infections by Diabetes may also be associated with a component approximately 52%, to $146 million. Expenditures for male urinary tract infection (in millions of $) and share of costs, by site of service Year 1994 1996 1998 2000 Totala 811. However, the mean time personal costs for both individual patients and the lost from work by men is somewhat greater. Expenditures for male Medicare benefciaries for the treatment of urinary tract infection (in millions of $), by site of service, 1998 Site of Service Total Annual Expenditures Age < 65 Age 65+ Inpatient 70. Expenditures for male Medicare benefciaries age 65 and over for treatment of urinary tract infection (in millions of $) Year 1992 1995 1998 Total 436. How can health care delivery be optimized to provide high-quality care while simultaneously decreasing costs and complications? Additional research on health services, outcomes, economic impacts, and epidemiological factors is needed to answer these challenging questions. More care is rendered to when irritative urinary tract symptoms occur girls than to boys, at a ratio of 34 to 1. Because other factors can cause care increased during the 1990s despite shorter lengths similar symptoms, the presence of symptoms in the of stay. Likewise, the fnancial burden is probably much higher because it presence of leukocytes in the urine is not proof of includes costs for outpatient services, imaging, other infection. Diagnostic methods in which there is a comorbidity that predisposes a vary markedly and depend on presentation, clinical child either to infection or to greater morbidity due suspicion, medical history, and local practice patterns. In the young child, there can years of age), older children (3 to 10), and adolescents be signifcant overlap in the clinical presentations (11 to 17). The rest of the cases are distributed Alternatively, urine can be obtained by sterile primarily among Proteus mirabilis, Klebsiella catheterization or suprapubic needle aspiration. Less common However, both of these techniques are invasive and infectious agents include gram-positive cocci, such as frequently met with parental disapproval. Viral infections are under-recognized because obtained, urine is examined with a reagent dipstick of diffculties with culture and identifcation, but for the presence of nitrates and leukocyte esterase. The course is typically is used to evaluate for the presence of obstruction characterized by discomfort and irritative voiding or stones, which can greatly increase the severity symptoms with rapid resolution following the and sequelae of infection. The primary appearance of the kidney can also be altered by the risk is that of recurrence or persistence. Ultrasound can assist constipation or voiding dysfunction are particularly in localizing the site of infection in the presence of prone to recurrence; 10% of these children develop renal abscess, parenchymal edema (lobar nephronia), a rapid recurrence following the completion of a or pyonephrosis. Renal scarring can lead confrming acute pyelonephritis and later for assessing to renal insuffciency and subsequent hypertension. Bacterial virulence it is nearly universally recommended for identifying factors include adhesins, K-antigen, hemosysins, vesicoureteral refux or other anatomic abnormalities and colicin. Bacterial colonization of the perineum that may contribute to future infection risk. Adhesins are specialized structures that enable the bacteria to adhere to specifc receptors on the uroepithelium. Such attachment leads to ascension into the urinary tract and promotes tissue invasion, 216 217 Urologic Diseases in America Urinary Tract Infection in Children infammation, and tissue injury. Adhesins may also The exact mechanism by which constipation exerts help promote intestinal carriage of more virulent its infuence on voiding is unclear, but it frequently bacteria, leading to perineal colonization. The relatively short length of the female urethra Successful host defense depends on the proper has traditionally been blamed for the increased risk of functioning of the urinary system. In the past, there was concern that a tight of the urinary tract is the frequent and complete ring narrowed the urethra, often prompting urethral emptying of urine in a low-pressure environment. Current evidence indicates This effectively fushes out bacteria prior to their that urethral constriction is not a reproducible establishment of clinical infection. It is anatomy (the short urethra in females and the prepuce clear that male infants with an intact prepuce are at in males). Colonization of bacteria on the inner children presenting with febrile infections. Present preputial mucosa occurs, but it is not clear whether in approximately 1% of the asymptomatic population this is the etiology of infection (8). Refux also bypasses one of the host defense risk of urinary infection during their frst 6 months mechanisms against upper tract invasion by allowing compared with circumcised boys, in addition to a less virulent strains of bacteria to reach the kidney. A fuller discussion but important host risk factor that can contribute of this controversial subject is beyond the scope of this to increased morbidity, persistence, and recurrence. Dysfunctional infection is based on symptoms, positive culture, or voiding refers to a learned pattern of behavior both; how accurate the method of specimen collection surrounding voiding that frequently begins with is; how accurate the history is, especially in young voluntary holding. Alternatively, it can present as an atonic associated with fever; and what the baseline rate of bladder with infrequent voiding and high post-void circumcision is in the population. Frequently, dysfunctional year of life (boys and girls), cumulative incidence at voiding can be compounded by chronic constipation. Age differences were most prominent among Girls have an increased risk of febrile infection patients requiring hospitalization. The rate of in the frst year of life, then the risk steadily declines inpatient hospital stays was 6. Their risk of nonfebrile commercially insured infants than the rate among infections is higher during childhood than during older children, and 11 times higher than the rate infancy.
Given the serious Food and Drug Administration has approved nature of many of the mosquito-borne dis- a feld trial to be conducted in a suburb of eases buy minocycline 50 mg mastercard antimicrobial therapy, insecticide use may be required where Key West purchase minocycline 50 mg otc antibiotic lupin, Florida buy 50mg minocycline visa infection 6 months after hysterectomy. Larvi- noted that the program presents no signif- cides can be applied to breeding sites discount minocycline 50mg fast delivery treatment for dogs with dementia. If successful, extreme conditions, pesticides can be directed the use of genetically modifed sterile male against adult mosquitoes. Anopheline However, a coalition of environmental public malaria vectors tend to rest on walls after interest groups has mounted a major cam- feeding; they then come in contact with the paign to block the feld trials. Consequently, Recent studies have shown that oral iver- insecticides applied to the insides of walls mectin given to humans and domestic animals affect only those mosquitoes that have fed will kill anopheline mosquitoes, notably the on humans and are potentially infected. This major African vector An gambiae, and could scheme does little to reduce mosquito popu- have a major effect on vector populations lations and usually has little environmental and malaria transmission. Systemic iver- impact; it does, however, reduce the inci- mectin appears to cause mortality in female 464 The Arthropods Ae. Individuals can become applied properly, they can reduce the annoy- sensitized to tabanid bites and suffer severe ance caused by the insects. Conse- The Tabanidae are a large family of blood- quently, the fys mouthparts can readily trans- sucking dipterans with a cosmopolitan distri- fer organisms to the next host after contami- bution. Bacteria causing anthrax from 7 to 30 mm in length, and are locally and tularemia, the protozoan T. Tabanids are strong fiers, capable of equine infectious anemia may be transmitted inficting painful bites, and in some areas by the tabanid fies, which act as mechanical of the world are considered serious pests vectors. Flies of the genus Loa loa is transmitted by African taba- Chrysops act as vectors of the flarial eye nids of the genus Chrysops, which include worm Loa loa in Africa and may be involved C. Microflariae of in the mechanical transmission of anthrax, the worm, ingested by female fies with the tularemia, and Trypanosoma evansi. When they reach maturity, they migrate to the Historical Information mouthparts and are deposited on the skin of a new host when the fy feeds again. Infectious Tabanids were implicated in the transmis- larvae burrow into the skin of the host after sion of anthrax as early as 1874, and of T. The role of tabanids as inter- mediate hosts and vectors of Loa loa was Control 28 verifed in 1914 by Robert Leiper. Tabanids are diffcult to control because Life Cycle of their diverse breeding sites. Their larvae develop in individuals should consider using repellents water or wet earth and pass through four to to avoid bites. Pupation occurs in is the standard for mosquito repellants there dry earth, and the quiescent pupal stage may are some people that are not able to tolerate last 2-3 weeks. Pathogenesis Muscidae: The House fly and Its Relatives Tabanid mouthparts are short and blade- The muscoid fies include insects that are 38. Insects 465 tsetse fy as the vector of African trypanoso- miasis while in 1898 Veeder demonstrated the importance of housefies as disseminators 30, 31 of various pathogens. Animal or human feces, garbage, decaying plant material, and sewage all provide suit- able substrates. The develop- ment from eggs to adults requires less than 10 days at summer temperatures. As a result of this reproductive potential, summer fy populations can be enormous. Some better- known members of this family are the house- fy Musca domestica, the stable fy Stomoxys Stomoxys calcitrans is a serious biting pest calcitrans. Only the tsetse ties, moist piles of grass clippings and weeds fies differ, in that their larvae develop singly provide ideal sites for larval development. Historical Information One of the plagues of Egypt described in the Old Testament consisted of swarms of fies. Gingrich 466 The Arthropods The egg-to-adult period during the summer lasts about 4 weeks, and a female may lay as many as 400 eggs during her life span. Although superfcially similar in appear- ance to housefies, stable fies have a promi- nent proboscis, which both sexes use effec- tively for sucking blood. The bite of the stable fy is initially painful but usually causes little delayed reaction. Stomoxys serves as a mechanical vector for 31 anthrax and some trypanosomes of animals. Calliphoridae, Cuterebridae, and The larva develops in three stages in utero Sarcophagidae: Myiasis-Causing Flies while feeding on milk produced by acces- sory glands of the female. Eventually, a fully Not all dipterans infict damage by the mature larva is deposited in a shady location, bite of adult fies seeking blood. The pupal stage of several families are pathogenic during can last up to 30 days and the resulting adult their development within the tissues of the remains inactive for 1-2 days after emerg- infested host. Certain spe- male and female tsetse fies are exclusively cies of fies are obligate parasites and require hematophagous, and both sexes are capable living tissue for development. Tsetse populations are myiasis when their eggs, deposited on food- relatively small and dispersed. Cheese-skippers of the by sight and follow animals, humans, or even family Piophilidae, rat-tailed larvae of the vehicles for long distances. They feed during Syrphidae, soldier fy larvae of the Stratio- the day, usually along paths or riverbanks. Insects 467 tobia hominis, the human botfy, parasitizes a number of mammals and is a serious pest of cattle in Central and South America. Female dermatobia fies capture various blood-sucking arthropods (usually mosquitoes or other fies), lay their eggs on the abdomens of their prey, and release these insects. When the fy or the mosquito carry- ing the eggs alights on a warm-blooded host, the eggs hatch, immediately liberating larvae onto the skin of the host. Myiasis: note the opening (black spot) in the skin which permits the maggot, burrowing in ous tissue, maintaining contact with the sur- the tissue below, to breathe. When or dead maggots in the vomitus, aspirates of the larvae complete their development after gastrointestinal contents, or stool specimens. During the phase within the tis- ing fesh for larval development occasionally sues, the maggots can cause intermittent pain deposit eggs or larvae on wounds or ulcers and secrete a foul-smelling material from the (Fig. Maggot therapy is the use of the larvae For human infestations, each maggot of certain fy species for selectively debrid- should be removed surgically. Administration began regulating the medici- ally become sensitized to the antigens of the 38, 39 maggot. In Europe, approxi- mately 30,000 maggot treatments are applied by coating their external spiracles with petro- annually. The fesh fies of the family Sarcophagi- dae contain several members of the genera Wohlfahrtia and Sarcophaga, which cause myiasis. Female fies in this family do not lay eggs, but deposit freshly hatched frst-stage larvae directly in wounds, ulcers, or even unbroken skin. Flies of the family Cuterebridae are obli- gate parasites, usually of wild and domestic animals. Human myiasis due to infestation with maggots of Cuterebra, normally asso- ciated with rodents, is not uncommon in the United States. Maggots of Cordylobia ents as individual larvae developing on vari- anthropophaga in the fesh of an infant. Screwworms continue to be a prob- left open and allowed to heal by secondary lem for veterinarian practioners and have intention. Several species of the family Calliphori- Flies of the genus Chrysomyia, the Old dae are obligate parasites, whereas others World screwworm, are important causes of cause only accidental myiasis. Cordylobia human and animal myiasis throughout Asia anthropophaga, the tumbu fy, is an uncom- and Africa. The emerg- prefer dead tissue; in the past, these maggots, ing larvae attach themselves to any host with reared free of pathogens, were used thera- 40-42 whom they come in contact and penetrate peutically for cleansing septic wounds.
Esto a menudo implica cruzar dos individuos que tienen el genotipo adecuado pero tal vez sean sexualmente incompatibles o estn separados fsicamente por grandes distancias order 50 mg minocycline with mastercard antibiotic injection for strep. Tambin puede ser ventajoso conservar a largo plazo los genes de un individuo valioso para incorporarlos peridicamente a la coleccin con el fn de maximizar su vigor gentico cheap minocycline 50mg visa treatment for sinus infection uk. Por la misma razn minocycline 50mg online antibiotic resistance graph, puede ser til cruzar individuos o poblaciones en centros de cra con individuos que viven en estado silvestre order 50mg minocycline free shipping antibiotics for sinus infection types. Los responsables de la gestin de especies silvestres deben tener en cuenta todas estas cuestiones. Desde hace ya bastante tiempo, las tecnologas reproductivas se consideran como una forma de ayudar al manejo gentico y la reproduccin de las especies amenazadas. Hasta el momento, las tcnicas de reproduccin asistida utilizadas de forma habitual en especies domsticas no han sido fciles de adaptar a las especies silvestres. Las diferencias entre especies en cuanto a la forma (anatoma/morfologa) y la funcin de la reproduccin (mecanismos que regulan el xito reproductor) limitan la aplicabilidad prctica de dichas tcnicas para la obtencin de progenie. Por lo tanto, el factor limitante es la falta de conocimientos bsicos sobre miles de especies que no han sido objeto de estudio, lo cual constituye la base esencial para la mejora de la reproduccin. Actualmente, existen claras evidencias de que las tecnologas reproductivas son de gran utilidad para estudiar cmo se reproducen las distintas especies, sobre todo cuando se defnen mecanismos nuevos y nicos. En este captulo, se analiza la situacin y relevancia de distintas tecnologas reproductivas tiles o prometedoras para felinos silvestres, con el fn de conseguir mejoras en su reproduccin, gestin y conservacin. Las tecnologas reproductivas son particularmente valiosas para esclarecer dichas diferencias fundamentales en las funciones biolgicas bsicas. Incentives largely have been derived from commercial efforts to increase livestock production and addressing human health issues. The ability to cryopreserve sperm and embryos permitted livestock managers and human couples to regulate the timing of offspring production, sometimes spread over generations. Compared with assisting livestock and humans, management and conservation of wildlife species have more complex expectations and logistics. For endangered species maintained ex situ, the aim is not only to produce more young, but offspring of known provenance and genotype that will preserve species integrity. This often requires the breeding of individuals of appropriate genotype, but which may be sexually incompatible or physically separated by distance. It also may be advantageous to preserve the genes of an individual for long durations to be periodically infused back into the collection to maximize genetic vigor. Reproductive technologies have long been considered a means of assisting in the genetic management and propagation of endangered species. So far, techniques that are routine in domesticated species are not easily adapted to wildlife. Species differences in reproductive form (anatomy/morphology) and function (mechanisms regulating reproductive success) limit practical applicability. The limiting factor is the lack of basic knowledge about thousands of unstudied species, the essential foundation to allow reproduction to be enhanced. There is excellent evidence that reproductive technologies are most useful as tools for studying how different species reproduce, especially defning unique mechanisms. Here, we review the relevance of various reproductive technologies for improving reproduction, management and conservation of wild felids. It is clear that species within the Felidae family vary markedly in reproductive mechanisms. Reproductive technologies are most valuable for elucidating these fundamental differences in basic biological function. The causes of population declines largely are related to habitat loss and fragmentation, although some wild cat species continue to be relentlessly persecuted by humans. While declines in wild felid numbers are signifcant, cats in general have the advantage of being charismatic, and their predatorial features (even the homicidal trait of 295 some of the great cats) intrigues us. In short, people generally like or at least tolerate felids, and this interest is advantageous to scientists who study and conserve wild felids. The public often is sympathetic to saving the worlds wild felids, and this attention often can be translated into helpful conservation policy or even fnancial support. Because reproduction is a key factor to species success, understanding how cats reproduce T helps to produce strategies for conservation and management. Much of the work in our laboratory is driven by the value of the domestic cat as a human biomedical model, especially for metabolic defects analogous to human congenital errors (e. However, most interesting have been the comparisons in reproductive phenomena between the domestic cat and its wild counterparts, as well as examining the utility of reproductive technologies for propagating and improving genetic management. Reviews of the roles of the reproductive sciences and related technologies for wild animal species are available from many sources, the most complete being a compendium for diverse taxa by Holt et al. There are two recently published articles on the value of conventional reproductive technologies for wildlife (Pukazhenthi and Wildt, 2004) as well as emerging techniques (Pukazhenthi et al. In this chapter, we share highlights of more than 25 years of experience on the value of such technologies for understanding, managing and conserving wild felids. This was a particularly serious gap in information because cats evolved throughout the world from within varied habitats and into wonderfully diverse morphotypes. Everyone assumed that all cats reproduced in a similar fashion, that is, males produced sperm throughout the year, but females were seasonal breeders and induced ovulators (the ova released in response to copulation). As recently as 1980, there were no clues about hormonal control of reproductive events in wild cats. Most scientists believed that it would be virtually impossible to study hormonal patterns in, for example, tigers. Zoos were realizing the need to become conservation catalysts rather than wildlife exploiters. It suddenly was anathema to take from nature, but rather to focus on developing self-sustaining wildlife populations that, in turn, were ambassadors for the wild that served to educate the public. If no more animals were to be removed from nature, then managers soon realized the need to develop state-of-the-art approaches for maintaining healthy populations of these complex species in artifcial environments. The concept of Species Survival Plans emerged, essentially the formation of zoo consortia that shared animals for breeding to maximize genetic heterozygosity. While some species (lions and tigers) seemed to breed at whim, others defed reproduction. Additionally, managers soon learned the insidious effects of poor husbandry, especially the adverse impacts of inbreeding. Besides behavioral challenges, other factors were emerging as important regulators of reproductive success. Early studies revealed inherently low amounts of genetic diversity in some wild felid species unrelated to zoo breeding but originating from population bottlenecks in nature. Th e cheeTah, o n e o F several Felid s p ec i e s /s u b s p ec i e s w i T h l o w geneTic variaTion T h a T r o u T i n e ly ejaculaTes h i g h p r o p o r T i o n s o F p l e i omo r p h i c (m a l F o r m e d ) s p e r m a T o z o a (p h oTo g r a p h b). Thus, there was a broad menu of factors to study and signifcant motivation from two directions, one being simply intellectual curiosity and the other being Fi g u r e 3. In retrospect, our laboratorys contribution to the study of wild felids was grounded in extensive prerequisite studies of the reproductive biology of the domestic laboratory cat. Begun in 1975, our early investigations of gonadal and gamete function, hormonal profles, behavior and assisted breeding provided us the fundamental information (and confdence) to expand studies to many wild felid species. Efforts were bolstered through partnerships with zoos and wildlife reserves throughout the world. We encountered a common interest wherever we went, agreement that these magnifcent species deserved immediate research attention. The details of the important fndings in wild felid reproductive biology are beyond the scope of this chapter. However, areas of signifcant discovery by us and other laboratories included: tH e I m P o R t a n c e o f s P e c I e s -sPecIfIcIt y cats evolved unique reproductive traits that no doubt maximize reproductive ftness within their normal wild niche. For instance, spontaneous (non-copulatory induced) ovulation is not uncommon in certain wild species (i. The female ocelot and margay show distinctive ovarian cycles throughout the year, contrasted to the tightly regulated Pallas cat that generally cycles for only two months annually.